BOSTON -- That pained look on Dwyane Wade's face as he watched his potential game-winning 3-pointer bounce off the rim? We've seen that before, as recently as the first round of the playoffs.

Those raised arms and confused looks during possessions when the Boston Celtics were pulling away early? We've seen plenty of those over the past two seasons.

The questionable late-game execution, the constantly changing starting lineup from game to game or even half to half? That's been a constant with the Miami Heat as well.

It doesn't matter that this was Game 4 of the Eastern Conference finals in the second year of the Heats' big three era. This team, apparently, is destined to be ever-changing, rarely settled and always making things much more difficult as it searches for that coveted championship.

After missing eight straight games, Chris Bosh may be back in the Heat's lineup in Game 5. Jesse D. Garrabrant/Getty Images

Granted, Sunday's game had its share of oddities it in it, regardless of the participants. Paul Pierce and James, each team's top scorer, fouled out of a game filled with questionable calls in both directions. And the Heat were still without Chris Bosh.

But in a game this tight, in such an emotional, meaningful setting, it's no wonder the team with more continuity and a better history of success in these situations came out on top to tie the series at two.

The Heat went with its fourth different starting lineup since Bosh went down in Game 1 against Indiana -- one that changed at halftime when Udonis Haslem replaced Joel Anthony to start the third quarter.

The changes kept Heat coach Erik Spoelstra continually tossing out groups that weren't entirely comfortable playing with each other -- at least not in a raucous TD Garden against a desperate and resilient Celtics team.

One game after Haslem played just 16 minutes, he played 36 major minutes in Game 4, continuing Spoelstra's unpredictable decisions involving the player often regarded as the heart of the team.

One game after Mike Miller played 21 minutes and was critical in the Heat's late comeback attempt, the Heat's primary 3-point threat played just 11 minutes and managed only a bucket in that time.

And in large part because of foul trouble to Mario Chalmers, rookie Norris Cole was handed crucial second-half minutes, which wound up working in the Heat's favor, but not without drawing the ire of James during that run.

For James, it's almost become routine to have no routine when it comes to the Heat's playing rotation.

"We don't know," James said. "For our starting lineup, it's been like that the last two years. We have guys in and out of the lineup, no matter what part of the season it is.

"At times, it's difficult to work with that. At the same time, we have to just figure it out. Whoever is starting, whoever is coming in needs to make plays."

The later games get for Miami, the more difficult it seemingly becomes to make any sort of play.

The Heat had two more failures in Game 4, one significantly clumsier than the other.

Near the end of regulation in a tie game, the Heat eventually got the ball to James, initially with just his defender on the strong side of the floor. Yet James didn't attack quickly enough, allowing Kevin Garnett to double-team him. James dribbled to his right and found Haslem on the baseline, but not before Garnett deflected the pass -- James said Garnett got a piece of his wrist -- forcing Haslem to put up a difficult, contested shot as the clock expired.

And in the game's final possession, the Heat tried to get a game-winning 3-point attempt from Mario Chalmers, but Wade didn't have the angle to find his teammate for the split second he was open. That left Wade to find his own shot, which he did -- a 3-pointer that came up just short.

While Wade did get a respectable look (aren't we always begging for James to take those game-winners and criticizing him when he hits an open man in that situation instead?) it was further evidence that the Heat have yet to establish any comfort level, no pet plays that this group can rely on, in such settings.

This team is determined to find success the hard way.

"We've all played in different positions, and versatility is one of the strengths that this team has," Haslem said, trying to explain why random rotations shouldn't necessarily be a problem for the Heat, even in critical times as these. "We can put guys in different places and guys should know what to do when they're out there."

That sounds great in theory, but if the Celtics can teach the Heat anything, it's that continuity and familiarity can go a long way. And Miami tends to find itself in unfamiliar situations more often than any other team in this position.

While the Heat might not have found a bunch of answers to these repetitive questions in Sunday's overtime loss -- and things might get even trickier if Bosh is activated for Game 5 as is now expected -- Spoelstra might finally have come to the realization that playing Haslem heavy minutes is a must.

Before Game 4, the Heat were 5-0 in playoff games in which Haslem played 20 minutes or more. In his 36 minutes Sunday, Haslem managed 17 rebounds, 12 points, 2 assists and a steal.

"I thought UD was amazing tonight, starting the second half," James said. "He did everything and more tonight, rebounded the ball, made shots. He played like a warrior."

And from Haslem, the Heat might've finally learned what it'll take to beat this Celtics team -- an older group that has been playing like the more desperate, energetic team for the past three games of this series.

"We can't tweak our effort," Haslem said. "There's nothing coach can do about effort. We have to have that from start to finish."

It's no coincidence that Haslem got 23 of his minutes after halftime, and the Celtics scored just 32 points in that span after putting up 61 in the first 24 minutes.

"We can't go out there cruising," Haslem said. "We can't be cool. We can't take our time. From start to finish, it's got to be all-out effort."

So while the Heat leave Boston with a lot of the same issues they've had for two full seasons now, they might go home knowing how to make them non-factors as they try to reach a second straight NBA Finals.